Drying machine



March 26, 1946. E. DAVIS 2,397,091

DRYING MACHINE Filed May 5, 1942 4 Sheets-Sheet 1 FIG. l

JOOOOO INVENTOR ERNEST DAVIS BY wm ATTO RNEYS March 26, 1946. E. DAVIS 2,397,091

DRYING MACHINE Filed May 5, 1942 4 Sheets-Sheet 2 INVENTOR ERNEST DAVIS zMdM/W ATTORNEYS March 26, 1946. E. DAVIS DRYING MACHINE Filed May 5, 1942 4 Sheets-Sheet 3 INVENTOR ERNEST DAVIS wwfiwv ATTORNEYS March 26, 1946.

E. DAVIS DRYING MACHINE Filed May 5, 1942 4 Sheets-Sheet 4 INVENTOR ERNEST DAVIS MMZ ATTORNEYS Patented Mar. 26, 1946 DRYING MACHINE Ernest Davis, Syracuse, N. Y., assignor to The Prosperity Company, Inc.,

Syracuse, N. Y., a

corporation of New York Application May 5, 1942, Serial No. 441,820

7 Claims.

This invention relates to machines for removing residual solvent from articles, after being dry cleaned, and the solvent for the most part removed, as by a centrifugal extractor. In removing the residual solvent and deodorizing the articles, heated air is passed through the articles, while in the machine, to vaporize the residual solvent, while the articles are being agitated in the machine. Such a machine is usually called a drying tumbler. A mixture of air and vapor of certain concentration or proportion of air and vapor is explosive. or inflammable when static or nearly static. It is not liable to explode or combust, if kept in rapid motion at a known flash point.

The invention has for its object a machine in which the air is passed through the solvent at such velocity, as by a blower, that an explosion can not occur, or if it does occur is extinguished by the velocity of outgoing air current, or is blown out, and means for extinguishing or smothering any explosion in the absence of an air current of suflicient velocity or upon failure of the air current.

Other objects appear throughout the specification.

The invention consists in the novel features and in the combinations and constructions hereinafter set forth and claimed; 1 y

In describing this invention, reference is had to the accompanying drawings in which like characters designate corresponding parts in all the views. a 1

Figure 1 is a sectionalview, partly diagrampermitting the passage of air therethrough and through the articles therein, and out of the drum through the outlet of the casing.

3 designates a door for a loading and unloading door opening 4 in a wall of the casing, the door opening being alined with the coaxial door opening in one end of the drum 2, the door opening or the drum 2 being confined, as by an annular flange 5. The door 3 is hinged at 6, as shown in Figure 7, to open and close about a vertical axis. The drum is mounted on a trunnion or axle 1 extending beyond the head thereof opposite to that in which the door opening is located, the axle being suitably journalled in hearings in a wall of the casing. The drum is actuated, preferably by an electric motor 8 which is connected to the axle I, as by a belt 9 running over a pulley III on the shaft of the motor and .over a pulley II on the axle. The casing I is provided with an air inlet conduit I2 opening into the upper side thereof above the drum and with an outlet I3 extending from the lower side of the casing, the outlet communicating with the inlet end of a blower casing matic, through 8 drying tumbler embodying this invention.

Figure 2 is a diagrammatic view illustrating the electrical controls and the wiring diagram therefor.

Figure 3 is a view similar to Figure 1 of a machine which is partly controlled by a timer.

Figure 4 is a detail and partly diagrammatic view illustrating the electric wiringutilized in Figure 3.

Figure 5 is a fragmentary view of the timer shown in Figure 4 illustrating its starting position before being set.

Figure 6 is a fragmentary timer.

Figure 7 is a fragmentary elevation of the door of the casing of the machine for the casing of the tumbler.

The machine or tumbler here shown includes an outer casing I, and a drum or clothes container 7 face view of the I 2 suitably mounted in the casing to move about a horizontal axis, the drum 2 being perforated for 55 ing I, outlet I3 and conduit I5,

I4, the outlet end of which communicates with a'conduit I5. The rotor I6 of the blower is actuated, usually by an electric motor II, through a belt I8 running over a pulley IS on the shaft of the motor I1 and the pulley on the shaft of the rotor I6. v

As here shown, the inlet I2 and the outlet conduit I5 have normally closed dampers 20 and 2| therein. These are opened andh'eld opened by the current of air created by the blower. If the blower stops for anyreaso'ri, as for instance, failure of the motor or by the breakage ofthe belt, as I 8, so that the current of. air through the inlet I2, casing I, drum ,2, 'outlet I3 and conduit it fails, these dampers return to their normal or full line position and control the flow of an explosion smothering or fire extinguishing medium, as

steam, to the casing. The motors 8 and H are idle and the energization thereof controlled by the closing of the door 3, which, when closed, closes the switch 29 in the feed circuits of the motors. This door-operated switch is a master switch and controls all the other branch circuits.

- Further, the door is automatically locked against opening by means responsive to the temperature within the casing I. In Figures 3 and 4, the flow of electric current through the damper controlled switches is also controlled by the master switch 2!! closed by the closing of the door 3.

The means for heating the air in the casing I,

that is, the air passing through the inlet I2, casas here shown,

comprises steam coils 22 located in the upper portion of the casing I abovethe drum 2 or between the inlet I 2 and the drum 2, these coils being connected to a pipe 23 from a steam supply, the pipe having a control valve 24. In Figures 1 and 2, the control valve is manually operated.

25 designates an emergency steam pipe leading from the steam supply pipe 23 between the valve 24 and the steam coils and having a nozzle 26 arranged to discharge into the casing I. Also, a normally closed, automatically operated, cut of! valve 21 is located in the pipe 25, this valve being opened by means controlled by the dampers 29 and 2|, when there is no air current through the and to hold the door locked until the temperature drops to a predetermined low.

The master switch 29 is located in the feed circuits for the motors 8 and I1, this switch being open when the door is open, and closed by the closing of the door, it being closed againstthe action of a returning spring 39. After the articles have been loaded into the drum 2 and the door 3 closed, a projection 3| on the door engages an arm 32 of the switch 29, closing the switch so that a current passes from feed wire 33 through wires 34 and 35 to the switch 29 and through the switch and wire 36, wire 39 to the motor l1 and thence through wire 49 to wire 31 and the other feed wire 38 and also the current passes from the switch 29 through wire 36, wire 42 to the motor 8 and to wire 4| and return wire 31. Hence when the door 3 is closed, the motors l1 and 8 are energized, the motor |1 causing the blower to operate and create a. current of air through the casing I and the motor 8 to move the drum 2 to tumble the articles therein. When the door is closed, and preferably after the door is closed, the operator opens the steam valve 24 by hand, so that steam flows through the heating coils v22 and the air is heated, as it comes from the inlet l2 and vaporizes and absorbs the solvent from the articles. The current of air created by the blower l4 causes the dampers 29 and 2| to swing to open position and remain in open position as long as there is an effective air current. The velocity created by the blower is such that the air is drawn. through and blown out before the explosive mixture is formed or a flame can be propagated, or if an explosion does occur, it is blown out by the current of air. If, however, the current of air fails, means is provided for immediately projecting into the casing "I, an explosion smothering or fire extinguishing medium, as steam. The flow of steam is controlled by the dampers 29, 2|. The dampers operate switches 43, 44 in electric circuits, which control the opening of the valve 21 by its electroresponsive means or solenoid, these switches being closed, when there is no air current passing through the casing I, that is, when the dampers 29 and 2| are closed, and being opened into the dotted line position when the dampers are moved locking of the door.

air current created by the blower l4. The flow when closed, is also controlled by a switch operated by the thermostat, which controls the The wiring for these switches 43, 44 will be described after the thermo-responsive means for locking the door closed is described. The thermoresponsiveelement 28 may be of any suitable construction. It operates through a bellows 45 to move a locking bolt 46 into interlocking engagement with the free edge of the door 3 when-the door is closed, the locking element or bolt 46 being spring-pressed to its unlocked position. I

The operation of the thermo-responsive element 28 under the rising temperature also operates to close a switch 41. After the door 3 is closed, and hence the motors 8 and I1 started, and the steam valve 24 having been opened, the air passing through the casing becomes heated, causing the thermo-responsive element 28 to operate the locking bolt 46 to lock the door closed and close the switch 41. This switch 41 is connectedvin series with the switch 43 operated by the damper 29, which is also in series with the windings of solenoid 48, which operates the valve 21 and the switch 41 is also connected by wire 49 to the feed wire 33 through switch 44 of the damper 2 The solenoid 48 is connected by wire 59 to the feed wire 38. When the switch 41 closes and in the normal operation, the switches 43, 44 are opened by the dampers 29 and 2|, nothing happens but in the event of failure of velocity of air current created by the blower M, the dampers 29 and 2| close, and hence close the switches 43, '44 so that the current passes as follows: wire 33 through wire 5|, closed damper operated switch 44, wire 49 through the closing switch 41, wire 52 through closed damper closed switch '43, wire 53 through the windings of the solenoid 48,

through wire 59 to the other feed wire 38, so that upon energization of the solenoid 48, the valve 21 is open, and steam is projected through the pipe 25 and nozzle 26 into the casing to extinguish any flame or smother any explosion in the casing The operator is prevented from opening the door 3 until after the air temperature of operative position by the current of air through the casing so that the flow of fire and explosion smothering medium is permitted only when the predetermined temperature is-reached within the casing, and there is not sufiicient air current to actuate the damper 29 or 2| to open the switch 43 or 44.

As a precautionary measure, in case an explosion or a fire should occur within the casing while the blower is in operation, and hence the dampers 29 and 2| in open position and the switches operated thereby open, means controlled by the high temperature caused by the explosion or fire is provided for extinguishing the same.

This means comprises a nozzle 55 directed to the casing and. connected by a pipe 56 to the steam pipe 23 and having a normally closed valve 51 and eld in their open dotted line Position y he therein, which is opened by a thermo-responsive device 58 located in the casing l and operatively connected'to the movable member of the valve to open the valve, when the temperature rises above a predetermined high. 1

In Figure 3 is shown a construction in which the steam valve 59, corresponding to the hand operated steam valve 24, is automatically operated upon the closing of the door 3 and upon the setting of the timer for stoppi the machine, after a predetermined working period. 60 designates the timer, which is operable to set the machine to run for different time periods, 'say from five to forty minutes, the length of time being selected by the operator for the quantity and character of the load to be cleaned. The timer operates switches in circuits for controlling the valve 58 leading to the steam coils and also for controlling the operation of the emergency steam valves, but the flow of current through these circuits is dependent upon the closing of the door 3 or the master switch 28, which is closed by the closing of the door 3. The setting of the timer 80 also operates a door locking bolt 68, corresponding to the locking bolt 46, for locking the door closed.

SI and 62 designate switches in different circuits, these switches being closed by the setting of the timer. The switch 6| is closed by the setting of the timer and closes a circuit from the feed lines 33, 38 through the motors l1 and 8, through wires 35, 36, 31, 4| and 42, as in Figure 2, and to the electro-responsive device or solenoid 63, which operates the steam valve 59 in the line to the heating coils, through wires 64, windings of solenoid 83, wire 65, switch 6|, when closed by the setting of the timer 60, return wire 66, and wire 61 to the wire 41. The switch 62 closes a circuit through the wire 68 through the switch 43, wire 68 switch 44, wire 68"- to solenoid 48, these switches being those that are operated by the dampers 20 and 2|. The timer 60 and the switches BI, 82 are suitably mounted on the outside of the casing near the door opening, and the setting of the timer operates, when the door is closed, to close the switches GI, 62 and also to shift a locking bolt 69, corresponding to the locking bolt 46, into locking engagement with the free edge of the door 3, this being against the action of a suitable returning spring. The locking bolt 69 is finally locked from unlocking movement by the action of the thermo-responsive device 28, which operates a notched locking head 10 into interlocking engagement with the head or flange II on the locking bolt 69, when this bolt is in locking position holding the door 3 locked closed.

The timer itself may be of any suitable construction and includes a suitable casing with timer mechanism therein, and a dial or'handle 12-mounted on an endwisely movable rock shaft 13 extending into the casing. The dial is movable to rock the shaft a predetermined distance from zero position into a position corresponding to the time selected for the machine to operate and the timer is set in operation by axial movement of the shaft 13. The axial movement is transferred to a yoke 14 for operating the switches GI, 62 and also to operate a motion transmittin device, as an angle lever 15, which operates the locking bolt 69. While the door is in open position, block 16 prevents lockin bolt 69 from be-' ing operated. Thus, the timer 60 and switches BI, 62 are prevented from being operated while the door 3 is open. Upon the closing of the door, both motors are energized. Upon-starting oi the motors, the current of air created by the blower ll chine opens the dampers 20 and 2|, and thereby opens the switches 48, 44, which control the emergency steam valves. As long as these switches 43, 44 are open, the emergency steam valves are closed, but the steam valve 59 in the pipe to the steam coils 22 is automatically opened, upon the closing oi the door and the setting of the timer. As the air passing through the casing I becomes heated by the coils, the thermo-responsive device 28 acts to move the locking head 18 into interlocking engagement with the bolt 88 and lock the door closed. When the machine has operated the time period for which the timer is set, the rock shaft is automatically moved outwardly, opening the switches GI, 82 and also withdrawing the lever arm 15 away from the locking bolt 89, although the bolt remains held locked until the thermoresponsive element 28 cools oil sufficiently to withdraw'the locking head I0 and permit the door. 3 to be opened. Upon the opening of the door 3, the circuits through the motors 8 and [1 are opened so that the machine stops.

The spring 80 against which the door 8 is closed tends to open door 3 when the lockin bolt 69 is automatically withdrawn, thus, opening switch 28 and closing the blower motor l1 and tumbler motor 8. It will be understood that after steam has been cut off from the heater coils 21, the blower motor l1 continues to run until the temperature is reached in the drum, when the thermo-responsive element 28 operates to release locking bolt 69. v

In either construction, ii. at anytime a fire or explosion should develop within the casing l the excessive heat created thereby will be effective upon the thermo-responsive device 58 to open the steam valve 51 and permit steam to be projected into the casing I. This is an entirely independent operation from the operation of the emergency steam valve 21 which is opened when the air current through the casing l drops and permits the damper operated switches 43, 44 to close and permits steam to enter the casing I through the pipe 25.

What I claim is:

1. In a drying machine for removing from articles residual solvent which vaporizes and forms an explosive mixture with air, said machine including a casing having an air inlet, and an outlet through which the air and vapors are passed, and means for heating the air passing through the casing; the combination of a loading door for said machine, means operable to create and maintain a current of air through the inlet in the casing and out through the outlet, means operated by the door in closing for controlling the operation of the current creating means, thermoresponsive means in the casing, 'means operable to supply an explosion smothering medium to the casing, means for controlling the flow of said medium to the casing when a predetermined temperature is reached in the casing, the last means including a part operable into operative position by the thermo-responsive means, and a second part normally in operative position and shiftable out of operative position by the current of air through the casing, whereby the flow of said medium is permitted only when a certain predetermined temperature is reached and there is not sulficient air current to actuate the second part out of its operative position.

2. In a drying machine for removing from articles residual solvent which vaporizes and I forms an explosive mixture with air, said me.-

including a casing having an air inlet, and

an outlet through which the air and vapor are passed, and means for heating the air passing through the casing; the combination of a loading door for said machine, means operable to create and maintain a current of air through, the inlet in the casing and out through the outlet, means operable to efiect the operation of the current creating means, thermo-responsive means located within the casing, means operable to supply an explosion smothering medium to the casing including a normally closed valve, and electrically operated means for opening the valve, an electr c circuit for the electrically operated means, a normally' open switch in the circuit, means operated by the thermo-responsive means for closing the switch when a predetermined temperature is reached, a second normally closed switch in said circuit, and a part operated by the current of air through the casing to open the second switch, whereby both switches must be closed in order to energize the electrically operated means and open the valve.

3. In a drying machine for removing from articles residual solvent, which vaporizes and' forms an explosive mixture with air, said machine including a casing having an air inlet and an outlet through which the vapors are passed, steam heating coils located in the casing for heating the air passing therethrough, and a feed pipe therefor; the combination Of a loading door for said machine, means operable to create and maintain a current of air through the inlet and the casing, and out through the outlet, means operated by the door in closing for controlling the operation of the current creating means, thermo-responsive means located in the casing in the path of the heated air current, means operable by the thermoresponsive means for locking the door when a predetermined temperature is reached, a steam pipe having a nozzle arranged to discharge into the casing, a cut-ofi valve therein, actuating means for the cut-off valve, and means controlled by said means operated by the door in closing and by means normally operable by the air passing through the casing to operate the cut-01f valve operating means to close the cut-off valve and to actuate the cut-oif valve operating means to open the cut-off valve when the air current creating means is idle.

4. In a drying machine for removing from articles residual solvent, which vaporizes and forms an explosive mixture with air, said machine including a casing having an inlet and an outlet through which the vapors are passed; the combination of a loading door for the machine, means controlled by the door in closing to create and maintain a current of air through the inlet and the casing, and out through the outlet, means also controlled by the door in closing and operable to supply an explosion smothering medium to the casing, and means operated by the current of air through the casing for controlling the flow of said medium to the casing when the door is closed,the last means including a part normally arranged in position toefiect the flow of. said medium, when the door is closed, and movable into position to prevent the flow of said medium by the current of air created by the current creating means.

5. In a drying machine .for removing from articles residual solvent, which vaporizes and Y closed, cut-oil valve therein, and means also controlled by the door in closing and operated by the current of air when the door is closed for controlling the opening of said valve to permit the flow ofsteam to the casing,'the last means in: cluding a part normally arranged in position to effect the flow of said medium, when the door is closed, and movable into position to prevent the flow of said medium by the current of air created by the current creating means.

6. In a drying machine for removing from articles residual solvent which vaporizes and forms an explosive mixture with air, said machine including a casing having an air inlet, and an outlet through which air and the vapors are passed, and means for heating the air passing through the casing; the combination of a loading door for saidmachine, means operable to create and maintain a current of air through the outlet, means for controlling the operation of the current creating means, thermo-responsive means in the casing, means operable to supply an explosion smothering medium to the casing, means for controlling the flow of said medium to the casing when a predetermined temperature is reached in the casing, the last means including a part operable into operative position by the thermoresponsive means, and a second part normally in operative position and shiftable out of operative position by the current of air through the casing, whereby the flow of said medium is permitted only when said predetermined temperature is reached, and there is not sufiicient air current to actuate the second part out of its operative position.

7. In a drying machine for removing from articles residual solvent which vaporizes and forms an explosive mixture with air, said machine including a casing having an air inlet and an out let through which the vapors are passed, steam heating coils located in the casing for heati g the air passing therethrough, and a feed pipe f r the Y coils; the combination of a loading door for said machine, means operable to create and maintain a current of air through the inlet and the casing and out through the outlet, means operated by the door in closing for controlling the operation of the current creating means, thermo-responsive means located in the casing in the path of the heated air current, means operable by the thermoresponsive means for locking the door when a predetermined temperature is reached, a steam pipe having a nozzle arranged to discharge into the casing, a cut-oil? valve therein, operating means for the cut-oif valve, and means normally operable by the air current passing through the casing to operate the cut-off .valve operating means to close the cut-oil valve and to actuate the cut-ofi valve operating means to open the cutofl valve, when the air current creating means is idle.

' ERNEST DAVIS. 

